Telephone system.



J. B. STEMM & G. E. SLADE. TELEPHONE SYSTEM. APPLICATION FILED APR. 111910.

Patented June 20, 1911.

1 63047 S/ade. m A M j a 0 W 6/? @barwey To all whom it may concern:

JACKSON B. STEMM, OF CHICAGO, ILLINOIS,

AND GEORGE E. SLADE, 0F BROOKFIELD,

MISSOURI.

' TELEPHONE SYSTEM.

Be it known that we, JACKSON B. STEMM and GEORGE E. SLADE, citizens ofthe United States, residing at Chicago, county of Cook, and State ofIllinois, and Brookfield, county of Linn, and State of Missouri,respectively, have invented certain new and useful Improvements inTelephone Systems, the following is a specification.

Our invention relates to telephonic apparatus. and has. for its objectthe provision of a telephone system particularly applicable of which foremployment in telephoning between two comparatively proximate points,the system being especially designed for use in substitution orreplacement of the ordinary speaking tubes which are generally used as amedium of communication between points not far removed.

A further object is the provision of a telephone system which will be ofextremely simple and inexpensive construction, in fact, a system whichmay be manufactured and installed at a cost considerably less than thecost of construction and installation of the ordinary speaking tubesystem; a further object being to provide a telephone system which willbe of great efiiciency in operation.

Other objects will appear hereinafter.

With these objects in view our invention consists in a telephone systemcharacterized as above mentioned and in certain details of constructionand arrangement of parts all as will be hereinafter fully described andmore particularly pointed out in the appended claim.

Our invention will be more readily understood by reference to drawingsforming a part of this specification, and in which,

Figure 1 represents the preferred organization of our improved system,and Fig. 2, a slightly modified form thereof.

In carrying out our invention we employ two similar diaphragms 1 whichare suitably mounted in holders 2-2,the latter be: 'ing designed'eachfor service both as an ear piece and a mouthpiece, in other words, as areceiver and a transmitter. Carried upon the outer side of-each of. thediaphragms 1 isa permanent magnet 3, preferably of the horse-shoe type,the arms or poles 4 thereof being extended perpendicularly outwardly.

5 indicate induction coils which are con- Specification of LettersPatent.

the accompanying Patented June 20, 1911.

Application filed A rn'n,19io. Serial No. 554,194.

nected in series in a circuit 6. The arrangement is such that themagnets 3 will induce a current into the coils 5, the intensity orstrength of such coils being governed by the position 'or proximity ofthe magnets relative to said coils. 'Hence the current induced will bevaried by the movement of the magnets toward or from said coils, thecurrent be ng stronger as the magnets approach saidcoils, the sainediminishing in strength as said magnets'recede therefrom. Said magnetsbeing fixed to the diaphragm 1, movement or vibration of the latter, ascaused by the impingement of sound waves thereon, will becommunicateddirectly to said magnets, hence the intensity of the induced currentwill be governed directly by the vibrations of said diaphragms. Thussounds produced at one of the diaphragmswill cause vibration of thelatter; this vibration, through the magnet carried thereby, producing anundulatory current or series of electric impulses in the circuit. Thisundulatory current will affect the other magnet to cause a correspondingvibration of the diaphragm connected thereto. Hence the sounds producedat one diaphragm will be reproduced at the other.

In Fig. 1 a metallic or wire conductor is employed in the circuit.However, with a view of'conducing to economy of construction, one leg ofthe metallic conductor may be dispensed with, if desired, as shown inFig. 2, and the resilient terminals 7 mounted.- A call b'ell system asis usual is also employed in conjunction with the telephone system. -Inthis system are included the circuit 8 in which are connected in seriesthe battery 9, bell 10, and push button or other suitable switch 11. Thecircuit 8, as illustrated, is so arranged that a leg of the metallicconductor of circuit 6 is utilized therein, the same serving as one ofthe legs of the former circuit. This arrangement is adopted only withthe end in view of producing a cheap construction.

While we have shown what we deem to be the preferable form of our systemwe do not wish to be limited thereto as there might be various changesmade in the details of construction and arrangement of parts describedwithout departing from the spirit of the invention comprehended withinthe scope of the appended claim.

2 i Q a 995,924

names to this specification in the presence of subscribing-Witnesses."

JACKSON B. STEMMJ GEORGE E. SLADE.,

Witnesses to signature of Jackson B.

Stemm:

ARTHUR A. OLsoN, JOSHUA R. H. Po'rrs. Witnesses to signature of GeorgeE. Slade:

RICHARD T. SMITHER, M. A. CooLEY.

